1. Field of the Invention
The present invention is directed to a gas-phase impregnation process, and, more particularly, to a process for caging a high concentration of diatomic molecules or substituted diatomic anions in solids. The present invention is also directed to uses of the process for fabricating various devices, such as solid-state lasers, magnetic (Faraday) rotators, Q-switches in the mid-IR range, etc.
2. Description of Related Art
Under proper vibrational excitation, a diatomic molecule or substituted diatomic anion caged in a solid such that all other internal degrees of freedom are frozen, other than vibrational, serves as a laser source through a cascade-type relaxation of its excited vibrational states.
The 2 to 5 .mu.m wavelength region is of interest to the development of solid-state mid-IR lasers. There are many diatomic molecules, as well as diatomic anions, whose fundamental vibration wavelength falls within the given range. However, the use of uncaged neutral molecules for gas laser applications suffers from two drawbacks:
(1) operating pressure must be low, otherwise, the vibrational output is collision-broadened (the lifetime of the excited--vibrational--state should be long compared to the time between collisions); and
(2) rotational degrees of freedom are active which provide a source of broadening and an added handle to radiationless relaxation of the excited state (vibrational) (energy stored in the vibrational mode is broken up into small parcels of the rotational modes which, in turn, are decimated further into the even smaller parcels of the translational).
At present, no known state-of-the-art techniques are known which are designed to trap a high concentration of diatomic molecules or diatomic anions in a solid.